Extend the expiry of an ENS subname in the NameWrapper. Subnames have their own expiry that cannot exceed the parent name's expiry. This tool extends a subname's expiry. Who can call this: - The parent name owner (always) - The subname owner (only if CAN_EXTEND_EXPIRY fuse is burned on the subnam...
Part of the Name Whisper server.
Free to start. No card required.
AI agents use extend_subname_expiry to create or modify resources in Name Whisper. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call extend_subname_expiry repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Name Whisper.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"extend_subname_expiry": {
"limits": [
{
"counter": "extend_subname_expiry_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Name Whisper policy for all 34 tools.
These attack patterns abuse exactly the kind of access extend_subname_expiry gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Extend the expiry of an ENS subname in the NameWrapper. Subnames have their own expiry that cannot exceed the parent name's expiry. This tool extends a subname's expiry. Who can call this: - The parent name owner (always) - The subname owner (only if CAN_EXTEND_EXPIRY fuse is burned on the subname) Use cases: - Extending subnames you've issued to users - Self-extending your own subname (if CAN_EXTEND_EXPIRY is set) - Keeping organizational subnames active. It is categorised as a Write tool in the Name Whisper MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Name Whisper MCP server in PolicyLayer and add a rule for extend_subname_expiry: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Name Whisper. Nothing to install.
extend_subname_expiry is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the extend_subname_expiry rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for extend_subname_expiry. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
extend_subname_expiry is provided by the Name Whisper MCP server (namewhisper/ens-tools). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 34 Name Whisper tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4,600+ MCP servers and 31,000+ tools scanned and risk-classified.